Three-component mixed working fluid for internal combustion engine waste heat recovery power cycle

Abstract

The present invention discloses a three-component mixed working fluid for an ICE waste heat recovery power cycle, wherein the three-component mixed working fluid consists of carbon dioxide, pentane and a refrigerant, the refrigerant is a high-performance environment-friendly refrigerant with GWP value which is lower than 1000 and ODP value which is 0, and the refrigerant is one selected from a group consisting of difluoromethane, fluoroethane and 1,1-difluoroethane; according to the selected refrigerants, the mass percentage of each component is as follow: the mass percentage of CO2, pentane and difluoromethane are 30-70, 10-20, and 10-60; the mass percentage of CO2, pentane and fluoroethane are 30-70/10-20/10-50; the mass percentage of CO2, pentane and 1,1-difluoroethane are 10-70/10-30/10-60. The present invention has good environmental performance, safety performance and thermodynamic performance, and the thermal efficiency is higher than 12% of prior art; and the present invention further has good ability of synergistically recovering waste heat of engine coolant and gas, thus reaching 100% utilization rate of engine coolant, and more than 60% utilization rate of gas. The critical temperature of the three-component mixture is obviously higher than that of CO2, the cooling conditions of the system are relaxed, and the conditions for the waste heat recovery system for vehicles are satisfied.

What is claimed is: 
     
       1. A three-component mixed working fluid for an internal combustion engine waste heat recovery power cycle, wherein the three-component mixed working fluid for the internal combustion engine waste heat recovery power cycle consists of carbon dioxide, pentane and a refrigerant, the refrigerant is a high-performance environment-friendly refrigerant with GWP value which is lower than 1000 and ODP value which is 0, and the refrigerant is one selected from a group consisting of difluoromethane, fluoroethane and 1,1-difluoroethane; according to the selected refrigerants, the mass percentage of each component is as follow:
 when the refrigerant is difluoromethane, comprising 10-20% by weight of pentane, 10-60% by weight of difluoromethane, and the rest is carbon dioxide; 
 when the refrigerant is fluoroethane, comprising 10-20% by weight of pentane, 10-50% by weight of fluoroethane, and the rest is carbon dioxide; 
 when the refrigerant is 1,1-difluoroethane, comprising 10-30% by weight of pentane, comprising 10-60% by weight of 1,1-difluoroethane, and the rest is carbon dioxide.